利用傅里叶变换红外光谱(FTIR)对5种不同类型的土壤进行了研究, 结果显示, 其红外光谱主要是由碳酸盐、硝酸盐、磷酸盐、锰酸盐等无机盐类, 黏土矿物及有机质的振动吸收带组成。五种土壤的红外光谱在1600～750 cm-1范围内呈现出差异, 作一阶导数处理后, 发现其差异主要表现在1440 cm-1、875 cm-1及798～780 cm-1附近。选取1600～750 cm-1范围内的一阶导数数据运用Matlab 2010来实现主成分分析, 前两个主成分累计贡献率达到90.14%, 利用这两个主成分作二维散点分布图, 结果表明该分布能对这五种土壤进行有效分类, 这为土壤鉴定提供了快捷的光谱手段, 同时表明傅里叶变换红外光谱技术用于对土壤的研究, 且具有测定快速方便、无损、准确等优点, 具有较大的应用潜力。

Fourier transform infrared spectroscopy (FTIR) was used to study five different types of soil, the results showed that the infrared spectra of soil were mainly composed of the absorption band of inorganic salts, such as carbonate, nitrate, phosphate, manganate and so on, clay minerals, and the organic matter. The FTIR spectra of five types of soil are similar on the whole, but they present obvious difference in the range of 1600~750 cm-1. According to the first derivative spectra of five types of soil, the differences were mainly found displaying in the range of 1440 cm-1, 875 cm-1, 798~780 cm-1. The first derivative data of the range of 1600~750 cm-1 were selected to use the Matlab 2010 to implement the principal component analysis, the contributing rates of the first two principal components had reached 90.14%, which can reflect the main information in the spectra. The two-dimensional distribution was made by plotting these two principal components as scores plots, which provided a reliable and rapid method for the identification of soil type. It is demonstrated that FTIR technique is rapid, nondestructive, convenient, accurate and has a great potential for application.